Apparatus for dephasing textured yarn

ABSTRACT

This invention relates to dephasing multifilament single end crimped yarn. The dephasing is carried out in an apparatus wherein the crimped yarn is passed between a plate and a rotatable roll which are mounted so as to exert a substantially constant pressure on said yarn regardless of variations in yarn thickness.

I United States Patent [151 3,667,090 Mazzone June 6, 197 2 [5 APPARATUS FOR DEPHASING References Cited TEXTURED YARN UNITED STATES PATENTS [721 Charla 3,426,407 2/1969 Constantine ..2s 1.5 [73] Assignee; Stevens & Co Inc" New York, NY. 3,430,295 3/1969 Dixon l9/65 T 3,465,399 9/ I969 Sokolowslq et al 1 9/65 X T Flledr m- 9, 1970 3,491,409 1/1970 Miller ....19/65 T [211 App], N0.2 70,776 3,497,920 3/1970 Brownell ..28/l CF Rehned A li ti Data Primary Examiner-Louis K. Rimrodt AnorneyMichael T. Frimer and Charles Stein [60] Continuation-impart of Ser. No. 57,737, July 23,

l970. which is 21 division ofSer. No. 7l6.533. Mar. 27, I968, Pat. No. 3,546,744.

57 ABSTRACT This invention relates to dephasing multifilament single end crimped yarn. The dephasing is carried out in an apparatus wherein the crimped yarn is passed between a plate and a rotatable roll which are mounted so as to exert a substantially constant pressure on said yarn regardless of variations in yarn thickness.

7 Claims, 4 Drawing Figures PATENTEDJUN 61912 3.661090 FIG.2.

INVENTOR CHARLES P. MAZZONE ATTORNEY I APPARATUS FOR DEPIIASING TEXTURED YARN This is a continuation-in-part of my U.S. application Ser. No. 57,737, filed July 23, 1970, which in turn is a division of U.S. application Ser. No. 716,533, filed Mar. 27, 1968, now U.S. Pat. No. 3,546,744, granted Dec. 15, 1970.

This invention relates to a method for improving the bulkiness of multifilament synthetic textured yarns and to an ap paratus for carrying out this method.

In recent years, there has been a continuous increase in the employment of synthetic polymer yarns, notably polyamide and polyester yarns, in various textile fields formerly depending on natural fibers or conventional rayon yarns, such as viscose or cellulose acetate. Yarn composed of a synthetic polymer possesses numerous excellent properties among which high tenacity, resistance to abrasion and uniformity are especially important. Nevertheless such yarn is apt to be regarded, in the case of some end uses, as inadequate in respect of a quality known as hand, feel, loftiness or fullness, a characteristic which is not easy to define because it is largely subjective and consequently a matter of personal opinion.

It is known that textile materials of improved hand can be obtained from multifilament synthetic polymer textured yarns which have been bulked by crimping the yarn and then dephasing the crimp, i.e., shifting the individual filaments out of their nested relationship. Crimping of the yarns can be accomplished by a number of methods such as gear crimping, stuffer box crimping, false twisting, jet bulking with an air stream and knit-de-knit.

A procedure for preparing a bulky yarn by dephasing crimped yarn is disclosed in U.S. Pat. No. 3,375,559 to Moyer et al. In the procedure of this patent the crimped yarn is threaded through a multiple tier arrangement of ceramic cylinders. Overlying the cylinders is a layer of compressible material which is urged downward by a pressure plate. A rubbing action which dephases the crimped yarn is obtained by drawing the crimped yarns through the arrangement of cylinders. A serious drawback to dephasing crimped yarn in the manner taught by Moyer et al., is that filaments are frequently broken, thus greatly reducing the strength of the yarn.

In accordance with the present invention there is provided a process and an apparatus which make possible the dephasing of crimped multifilament yarn at high speeds with a minimum of filament breakage. This is accomplished by running the crimped yarn between a plate and a power-driven roll which is rotating in the same direction as the yarn is moving, at a speed of about 1 to 3 times the speed of the yarn, the plate and the roll being mounted so as to exert a substantially constant pressure on the yarn regardless of variations in yarn thickness. The speed at which the yarn is run between the plate and the roll is maintainedsubstantially constant for each run, with this speed being determined by mechanical means acting upon the yarn after it has been dephased. The dephased yarn is wound on a takeup device with the yarn being maintained under a controlled tension while being so wound.

The invention will be more readily understood when the following detailed description is read in conjunction with the accompanying drawings.

FIG. 1 shows a side elevation of a crimped yarn dephasing apparatus embodying the principles of the present invention;

FIG. 2 is an enlarged view showing in detail the portion of the apparatus of FIG. 1 wherein the crimped yarn is dephased;

FIG. 3A shows the increase in bulkiness of a yarn which has been gear crimped and then subjected to the process of the subject invention. The gear crimped yarn prior to dephasing is represented by (19) while the dephased yarn is represented by 19a); and

FIG. 3B shows the increase in bulkiness of a yarn which has been knit-de-knit texturized and then subjected to the process of the subject invention. The knit-de-knit yarn prior to dephasing is represented by (15),while the dephased yarn is represented by (15a).

Referring now to FIG. 1, there is shown a crimped multifilament yarn which moves along a path from a supply package (12) through a dephaser (l4) and then to a constant speed wind-up cone (16). The speed of the yarn through the dephaser is substantially constant andis determined by the constant speed wind-up cone 16).

The tension on the yarn (10) as it feeds into the dephaser (14) should be in the range of about 0.01 to 0.5 grams/denier, a preferred range being 0.01 to 0.3 grams/denier. A satisfactory tension is obtained under some operating conditions without any adjustments; however, it is preferable to employ a tension regulating device such as the arrangement of snub bars (8) and (9), shown in FIG. 1. It is also necessary that tension on the yarn as it is wound onto a takeup'device such as cone (16) be within a specific range. This winding tension should be about 0.01 to 0.6 grams/denier, with a preferred range being 0.05 to 0.18 grams/denier. The winding tension is adjusted by tension regulator (18) which can be an arrangement of snub bars similar to that discussed above or any other suitable tension regulating device.

In the dephaser (14), the yarn is run between a power driven rotatable roll (20) which rotates in the same direction as the yarn is moving and a plate (22). Referring now to FIG. 2, it is seen that the plate (22) is rotatably mounted on pivot (26) so as to press the yarn (10) against the roll (20). As a result of this pivotal mounting the plate moves in a direction substantially perpendicular to the yarn path in response to variations in the yarn thickness. Thus, substantially constant pressure is maintained throughout each run regardless of variations in yarn thickness and uneven dephasing and excessive filament breakage are avoided.

The pressure exerted for a given run is determined by an adjustable weight means which changes the force tending to rotate the plate (22) about the pivot (26). In the embodiment of FIG. 2, the adjustable weight means is a lever arm (24) having a series of aperatures (30) therein through which a weight (28) can be attached. The pressure exerted by plate (22) can thus be adjusted by moving weight (28), adding additional weights, or replacing weight (28) with a difi'erent weight. Many variations of the adjustable weight means shown in FIG. 2 can, of course, be constructed by those skilled in the art, e.g., a lever arm having a weight slidably mounted thereon. However, it is necessary that the adjustable weight means be such that the pressure exerted by plate (22) can be accurately set and maintained. I

The pressure exerted by the plate (22) is preferably between about 10 to 300 grams. The degree of dephasing of the crimped yarn changes as the plate pressure changes. Thus, in order to obtain a homogeneous product it is necessary that the pressure be accurately set at the beginning of each run and then be accurately maintained throughout the run.

To prevent excessive filament breakage the surfaces of the roll and plate contacting the yarn should be relatively smooth. Satisfactory results can be obtained with slightly roughened surfaces such as with a matte finish, but the presence of engraved teeth or ridges cannot be tolerated. Additionally, the surfaces contacting the yarn should be made of relatively hard material such as metal, glass or ceramic.

The degree of dephasing is also dependent on both the speed of the yarn through the dephaser and the relative speed of the dephasing roll (20). In general, the dephasing roll is rotated at a speed of about 1 to 3 times the speed of the yarn.

The speed of the yarn through the dephaser should be determined by mechanical means acting upon the yam after it has passed through the dephaser. Particularly good results are obtained when the speed of the yarn is set by the takeup device on which the dephased yarn is wound. Preferably, the takeup device should pull the yarn through the dephaser at a substantially constant speed, i.e., the speed at which the wound package of the takeup device rotates should change as the diameter of the wound package increases in order to maintain a substantially constant linear yarn speed. Such constant speed takeup devices are well-known and are found on a number of commercially available winders. If the constant speed takeup device of the embodiment of FIG. 1 is replaced by a takeup device in which there is no speed adjustment correlated with the diameter of the wound package, i.e., the linear speed of the yarn progressively increases as the package is wound, the quality of the yarn produced is not as good but is still acceptable for some purposes. If the yarn runs through the dephaser at a speed which is uneven or jerky, the product obtained is of poor quality. 7

As seen in FIG. 2, the plate (22) is positioned so that the plate surface which contacts the yarn is perpendicular to the radius of the roll at the point where pressure is exerted on the yarn. This relative positioning is preferable for optimum dephasing. Guide means can, of course, be employed to assist in holding the yarn in the desired path. In FIG. 2, guide (34) is shown positioning yarn (10) just prior toits passage between the plate (22) and the roll The multifilament yarns dephased by the present invention can be made of a wide variety of polymers. Examples of a few of the many suitable polymers are polyamides such as poly(hexamethyleneadipamide)- and polycaprolatum; polyesters such as polyethylene glycol terephthalate, polyurethanes, polyethylene, polypropylene and cellulose acetate. The yarn should be of continuous filament construction and should be unplied, i.e., single end.

The crimped yarn to be dephased can be provided from a wound spool such as shown in FIG. 1, or from any other suitable package. For instance, when knit-de-knit yarn is used the yarn can be pulled directly from a knitted sleeve.

The following examples are given to further illustrate the invention, but it is to be understood that the invention is not to be limited in any way by the details described herein.

EXAMPLE 1 A knit-de-knit texturized 34 filament yam comprising polyethylene glycol terephthalate (polyester) having a denier of 150 was run through a dephasing apparatus such as shown in FIGS. 1 and 2 at a speed of 170 yards per minute. The dephasing roll was stainless steel provided with a chromeplatedmatte finish and had a diameter of 1 5/16 inches. The roll was rotated at the rate of 1,700 rpm with the direction of rotation being the same as that of the running yarn. The dephasing plate was made of aluminum oxide. Prior to entering-the dephaser the yarn was under a tension of 0.03

grams/denier. The plate pressure was 100 grams and the dephased yarn was wound onto the constant speed wind-up cone under a tension of 0.04 grams/denier. The speed of the yarn through the dephaser was controlled by the wind-up cone.

The resulting yam has a pleasant full hand and can be woven or knitted into soft, warm material.

EXAMPLE 2v A gear crimped (FIG. 3A) 234-filament cellulose acetate having at least 92 percent of its hydroxy groups acetylated (cellulose triacetate) 200-denier fiber was run through a dephasing apparatus such as shown in FIGS. 1 and 2 at a speed of 170 yards per minute. The dephasing roll was stainless steel provided with a polyurethane matte finish and had a diameter of 1 5/16 inches. The roll was rotating at the rate of 1,700 rpm with the direction of rotation being the same as that of the running yarn. The contact surface of the dephasing plate was made of polyurethane. Prior to entering the dephaser, the yarn was under a tension of 0.04 grams/denier. The dephasing pressure on the yarn was maintained at 20 grams and the dephased yarn was wound onto the constant speed wind-up cone under a tensionof 0.03 grams/denier.

The resulting yarn possesses a pleasant full hand and can be woven or knitted into soft warm material.

EXAMPLE 3 A knit-de-knit texturized,34 filament, 150 denier yarn comprising polyethylene glycol terephthalate was run through a dephasing apparatus such as shown in FIGS. 1 and 2 at a speed of 750 feet per minute. The dephasing roll was provided with a polished chrome surface and had adiameter of 1 5/16 inches. The roll was rotated at the rate of 3,000 rpm with the direction of rotation being the same as that of the running yarn. The contact surface of the dephasing plate was made of polished chrome. Prior to entering the dephaser the yarn was under a tension of about 17 grams. The plate pressure was 60 grams and the dephased yarn was wound onto the constant-speed wind-up cone under a tension of about 11 grams. The speed of the yarn through the dephaser was controlled by the wind-up cone.

The resulting yarn had a pleasant, full hand and was knitted into a soft material.

EXAMPLE 4 A knit-de-knit texturized, 34 filament, 70 denier yam coinprising polyethylene glycol terephthalate was run through a dephasing apparatus such as shown in FIGS. 1 and 2 at a speed of 750 feet per minute. The dephasing roll was provided with a polished chrome finish and had a diameter of 1 5/16 inches. The roll was rotated at a rate of 3,000 rpm with the direction of rotation being the same as that of the running yarn. The contact surface of the dephasing plate was also made of polished chrome. Prior to entering the dephaser the yarn was under a tension of about 17 grams. The plate pressure was 50 grams and the dephased yam was wound onto the constantspeed wind-up cone under a tension of about 1 l grams. The speed of the yarn through the dephaser was controlled by the wind-up cone.

The resulting yarn had a pleasant, full hand and was knitted into a soft material. 1

It will be apparent that many modifications and variations can be effected without departing from the scope of the novel concepts of the present invention, and the illustrative details disclosed are not to be construed as imposing undue limitations on the invention.

What is claimed is:

1. An apparatus for dephasing a multifilament single end crimped yarn, said apparatus comprising a. a plate and a power-driven rotatable'roll positioned so that the yarn to be dephased passes therebetween, said plate and said roll being mounted so as to exert a substantially constant pressure on said yarn regardless of variations in yarn thickness, said mounting including means pivotally mounting the plate for movement in a direction substantially perpendicular to the yarn path whereby said plate moves in response to variations in the thickness of the yarn between said plate and said roll, the relative positions of said plate and said roll being such that the plate surface which contacts the yarn is perpendicular to the radius of the roll at the point where pressure is exerted on the yarn,

b. a takeup device on which said dephased yarn is wound, said takeup device serving to pull said yarn between said plate and said roll at a substantially constant speed, and

c. means for maintaining the dephased yarn under a controlled tension as it is wound on said takeup device.

2. An apparatus as claimed in claim 1 including adjustable weight means associated with said plate which act to rotate said plate about said pivotal mounting up against said roll and control the amount of pressure exerted on said yarn.

3. An apparatus as claimed in claim 1 including means for controlling the tension of the yarn as it approaches said plate and said roll. 7

4. An apparatus for dephasing a multifilament single end crimped yarn, said apparatus comprising a. a plate and a power-driven rotatable roll positioned so A pivotally mounting the plate for movement toward and away from said roll in response to variations in the thickness of the yarn between said plate and said roll, the relative positions of said plate and said roll being such that the plate surface which contacts the yarn is perpendicular to the radius of the roll at the point where pressure is exerted on the yarn,

bv a takeup device on which said dephased and c. means for maintaining the dephased yarn under a controlled tension as it is wound on said takeup device.

5. An apparatus as claimed in claim 4 wherein the speed at yarn is wound,

7. An apparatus as claimed in claim 5 including means for controlling the tension of the yarn as it approaches said plate and said roll. 

1. An apparatus for dephasing a multifilament single end crimped yarn, said apparatus comprising a. a plate and a power-driven rotatable roll positioned so that the yarn to be dephased passes therebetween, said plate and said roll being mounted so as to exert a substantially constant pressure on said yarn regardless of variations in yarn thickness, said mounting including means pivotally mounting the plate for movement in a direction substantially perpendicular to the yarn path whereby saiD plate moves in response to variations in the thickness of the yarn between said plate and said roll, the relative positions of said plate and said roll being such that the plate surface which contacts the yarn is perpendicular to the radius of the roll at the point where pressure is exerted on the yarn, b. a takeup device on which said dephased yarn is wound, said takeup device serving to pull said yarn between said plate and said roll at a substantially constant speed, and c. means for maintaining the dephased yarn under a controlled tension as it is wound on said takeup device.
 2. An apparatus as claimed in claim 1 including adjustable weight means associated with said plate which act to rotate said plate about said pivotal mounting up against said roll and control the amount of pressure exerted on said yarn.
 3. An apparatus as claimed in claim 1 including means for controlling the tension of the yarn as it approaches said plate and said roll.
 4. An apparatus for dephasing a multifilament single end crimped yarn, said apparatus comprising a. a plate and a power-driven rotatable roll positioned so that the yarn to be dephased passes therebetween, said plate and said roll being mounted so as to exert a substantially constant pressure on said yarn regardless of variations in yarn thickness, said mounting including means pivotally mounting the plate for movement toward and away from said roll in response to variations in the thickness of the yarn between said plate and said roll, the relative positions of said plate and said roll being such that the plate surface which contacts the yarn is perpendicular to the radius of the roll at the point where pressure is exerted on the yarn, b. a takeup device on which said dephased yarn is wound, and c. means for maintaining the dephased yarn under a controlled tension as it is wound on said takeup device.
 5. An apparatus as claimed in claim 4 wherein the speed at which the yarn passes between said plate and said roll is determined by a mechanical means which pulls the yarn between said plate and said roll at a substantially constant speed.
 6. An apparatus as claimed in claim 5 including adjustable weight means associated with said plate which act to rotate said plate about said pivotal mounting up against said roll and control the amount of pressure exerted on said yarn.
 7. An apparatus as claimed in claim 5 including means for controlling the tension of the yarn as it approaches said plate and said roll. 